Materials & ConstructionThe box is Granadillo while the pieces are East Indian Rosewood and Ash. Beautifully made (although the top surface of my box had a slight blemish, probably just my copy) and the pieces fit very nicely without being too snug.

OverviewHere is another packing puzzle from prolific designer Goh Pit Khiam. Like most 2D packing puzzles, this one came un-assembled. However unlike a traditional packing puzzle, the pieces of the Checkbox have various protrusions which mesh with each other and the box (which has got a channel running along the insides). Thus, Checkbox is also an interlocking puzzle as well. Goh had mentioned to me that he had originally designed a 9 piece version with numbers 1 to 9, but felt it was too difficult to solve.The goal is to insert the pieces into the box AND form a checked pattern as shown in the photo. Right from the start, you can tell that orthogonal sliding of the pieces is required and no rotations are allowed. In fact no rotations are physically possible anyway.

Goh is famous for this sort of "look-simple-but-is-not" puzzles. It has just 4 pieces but I can assure you that it is very tricky to get the pieces into the box correctly to produce the final result. Some thinking is required to determine how the pieces interact with each other and vis-a-vis the box. A couple of times, I thought I had nailed it but the final piece going in either didn't form a checked pattern or couldn't fit.

DifficultyI would rate it as moderately difficult but rather tricky to assemble. It takes approximately 11 moves to get all the pieces in and there is a sequence to that. But once you get it right, a nice a-ha feeling! Taking the pieces out is much easier, hence the puzzle is shipped un-assembled.

Summary

A very nice (and cute) well made little puzzle with a similar theme to Bill Cutler's Slide Block Sliding Block puzzle. If you like packing puzzles with an added twist, this is a must-have. Great fun and you won't tear your hair out trying to solve it.

Wednesday, 27 April 2016

Manufacturer & AvailabilityCrafted by Tom Lensch. Limited copies may be available but I can't be sure. PM me if interested.

Type & Classification3D PackingDimensionsBox is 5cm x 5.7cm x 6cm. Each of the links in the chain is 4.7cm x 3.1cm x 0.8cm.

Materials & ConstructionBox is yellowheart while the chain links are cherry. Excellent construction, fit and finish. Tolerances are just right and everything fits nicely.

OverviewChain Store is an old design from Goh Pit Khiam and it wasn't until recently that working copies of the puzzle were produced. The goal is simple; to fit the chain links (which are all interconnected and you can't separate them) into the box flush with the top. Hence the very appropriate name "Chain" - "store". It's been described by John Rausch as a "one piece packing puzzle"...well, quite literally true isn't it?The links when stretched out look rather long and it is obvious that you can't just stuff them into the box. Because of the tight tolerances, any attempt to force in the links would most certainly result in jamming (and probably damage as well). According to Goh, there is only one solution to pack the links in. Sorry but Burr Tools doesn't work here (even with the "grouping" function).It is clear that the links must somehow be grouped together in a certain way to take up the smallest and correct size footprint in order to fit into the box just nicely. The links can be rotated in different ways and this is a necessary part of the solving process. But this arranging and grouping of the links is no walk in the park, despite only 5 pieces. In fact it is darn right difficult and I found myself trying a great number of combinations to no avail. Always, one link would be protruding a bit and refuse to go in the box. This puzzle requires you to solve the links outside the box before insertion.

DifficultyVery challenging puzzle. I don't know whether it was just my lucky day or not, but I managed to solve it in about 40 minutes. Got the 5 links all in their correct positions and popped it into the box. Still, I can imagine some puzzlers would take much longer than that. At the request of Goh, I have not placed a link here to the photo solution.

Summary

Goh has designed a number of challenging and interesting packing puzzles, including IPP award winning ones such as Dancing Shoes and Road Blocks. But Chain Store is perhaps the most unusual and unique amongst them. A fabulous puzzle with a great design concept. A must-have in any collection.

Materials & ConstructionLaser cut acrylic. Very precisely cut with sharp edges, resulting in an excellent quality puzzle. Tolerances are just nice and the combo colours of red, white, blue and black make the puzzle stand out.

OverviewSlide X was Iwahiro's (Hirokazu Iwasawa) IPP35 Exchange Puzzle in Ottawa, Canada last year. There are a total of 8 pieces; 4 white rectangles and 4 black "L" pieces. Together they cover a substantial part of the red tray.This is a sliding block puzzle with a bit of difference. Instead of moving the pieces from a start position to an end position as what most puzzlers are used to, the challenge is to form various silhouette shapes. A great and unusal design concept nonetheless!

The main challenge consist of a warm-up "practice run" (see photo) to change the silhouette of a "red cross" to a "U". This one takes 14 moves. Not a lot of moves but because now you are focusing on the "U" shape, the puzzle is harder than the 14 moves would suggest (at least for me). So what I did was to focus my attention on where the pieces should end up and tried to ignore the "U". Now for the main problem which requires a minimum of 48 moves, the instructions do not come showing the end position of the individual pieces. So the starting point is probably to pack the pieces into the tray to see how the "T" is formed. And then figure it out from there. A photo would certainly help! In any event, it was too difficult for me and I gave up after a number of tries. 8 pieces to slide is really no joke. But I did succeed in one of the other easier challenges on the separate problem sheet.

DifficultyThere are a total of 14 challenges in all with increasing levels of difficulty, ranging from 14 to 114 moves! I am not good at sliding puzzles. Notwithstanding, I think this one is really difficult especially for the higher level challenges. Definitely a sliding puzzle not to be missed by die-hard sliding puzzle enthusiasts.

Tuesday, 19 April 2016

Manufacturer & AvailabilityProduced by Buttonius Puzzles & Plastics. A number of interesting laser cut acrylic puzzles, some past IPP exchange puzzles are available for sale from their site. Matchless is currently available from Wil Strijbos for 20 Euros.

Materials & ConstructionLaser cut acrylic with steel screws and the match is blue coloured wood. Very well made and put together. Excellent quality. The option to use screws to clamp the several layers was a good choice otherwise the gluing would have been visible through the clear acrylic.

OverviewNow Matchless is a very interesting and unusual puzzle. This was Peter Hajek's IPP35 Exchange Puzzle in Ottawa, Canada last year. The goal of the puzzle appears simple enough; to remove the match from the box, but the execution much more difficult than you can imagine. As you can see from the photo, there are two holes (just large enough for the match to go through) on two sides of the box. And the initial reaction is to try to use dexterity and turn, tap and shake the box and hope the match would slip out of the hole. Which is what I did and in fact I did succeed after a little while of trying. Several other puzzlers whom I shall not name achieved the same result this way.

However Peter indicated to me there is a way that is far more "elegant" and effective for extracting the match (without tools of course) and when I tried it, I couldn't agree more.

DifficultyDifficult if you don't know the correct solution but very easy if you do! Definitely a nice change away from the usual genres of puzzles.

Materials & ConstructionSix pieces comprising three woods; ash, wenge and bubinga. Great looking! Excellent construction, fit and finish with tight tolerances. All the pieces slide and move very smoothly.

OverviewExternally it looks pretty just like an ordinary burr (save for the three pairs of different coloured sides) but the 6 pieces forming this puzzle are anything but ordinary. They are not your regular burr pieces with the typical notches and groves but rather odd shaped with loads of protrusions as you can see from the photo below.This is an extremely difficult puzzle to take apart with a level 26.9.5.2 solution, meaning it requires 26 moves to remove the first piece. I was stuck for quite a while during the opening moves trying to figure out things. However, something totally unexpected happened next. I am not sure if it is my copy that was a bit looser than intended (because my wooden puzzles are usually kept in a camera dry box for a few days prior to play). But midway through the solving, I was actually able (to my great and pleasant surprise) to rotate one of the pieces out without any force whatsoever. Having done that, the rest of the pieces came out quite easily thereafter. OK, so its not the way it should have been done and I am not sure how I did it...but too late...its over! Was it an accidental discovery of something in the puzzle that neither Derek nor Eric were aware off?[Edit 16 April 2016: I am informed by Derek that apparently this rotation is well known and certainly not intended]

Difficulty"Fiendishly difficult" is what Eric describes on his site. Fully agree. The movements of the pieces are absolutely dizzying! Without Burr Tools, my copy will have remained on the shelf in their separate pieces. If the rotation of that one piece had not been possible, I definitely would not have been able to take the Half Dozen apart. Even with the aid of Burr Tools, trying to reassemble the six pieces was still quite a handful (no pun intended).

Wednesday, 13 April 2016

DesignerDerek Bosch. Very well known in the community for his cylindrical burr designs range, see for example the Helical Burr. For his other works, click here. I just realized I do have a copy of his "Derek's Half Dozen"....stay tuned for a future post on this one.

Manufacturer & AvailabilityProduced by Steve Nicholls. May be available but in limited quantities. You can contact Steve here.

Type & ClassificationInterlockingDimensions16cm x 4.5cm diameter

Materials & Construction3D printed in plastic resin. Very well made and absolutely gorgeous colours. Mine's a bright yellow and purple. I saw other colourful combinations as well at IPP. Nicely presented in a transparent carrying tube.

OverviewLooking like a delicious ice lolly, you can probably guess why the puzzle is called Pole Dancers. No prizes here. The puzzle was also Steve's IPP35 Exchange Puzzle in Ottawa, Canada last year. The goal here is to separate the purple and yellow pieces from the rod. For this type of cylindrical puzzles, 3D printing is probably the best (and only) choice available. I seriously doubt if they can be made in wood. As I mentioned previously in my review of the Helical Burr, the manipulation of a 3D printed burr like this is never going to be as slippery smooth as a well made interlocking wooden burr. However, it is sufficiently slick for comfortable play and I did not experience any jamming. One of the advantages of 3D printing is that the puzzle won't expand in humid climates unlike their wooden cousins. In fact as I played more, the puzzle got quit "seasoned" after a while and the movement of the pieces became smoother overall.

Solving consists of pulling, pushing and rotating the pieces around the axis of the rod. The pieces are interlocked together via grooves and notches on their insides and the surface of the rod. Typically trial and error is required at the beginning to see how the pieces interact with each other. Careful observation of the movements is also necessary, particularly when you want to re-assemble the puzzle later. And remember the orientation of the pieces too. I don't know the exact number of moves as I lost count somewhere after the first 5 to 6. But by my estimation, I think its somewhere between 13 to 15 moves for full dis-assembly. Honestly the dance gets quite confusing halfway through!

DifficultyIts a difficult puzzle no doubt, but strangely I felt it was a bit less difficult than the Helical Burr which had four pieces (vs three for Pole Dancers) and even fewer moves. Maybe the Helical Burr was the first time I was playing with this sort of puzzle and hadn't gotten used to it yet.

While Helical Burr required only the removal of the first piece and the rest became pretty straight forward coming apart, Pole Dancers is tricky in the sense that you are not sure which end of the rod the two pieces emerge from (or is it from both ends?) and you get a bit confused halfway and need to back track once you hit a dead end. SummaryAnother great design here from Derek Bosch. Well made, colourful and a nice alternative to the usual rectilinear wooden burrs. And what an appropriate name!

Sunday, 10 April 2016

This weekend's puzzle play consisted of Symmetrick from Vesa Timonen of Finland and Four Triangles Five Shapes from Emrehan Halici of Turkey.

Symmetrick

Symmetrick was a Top 10 Vote Getter during the IPP33 Puzzle Design Competition in Japan. It was also Vesa's exchange puzzle during IPP32 the previous year. In case you didn't know, vesa is a very prolific designer with a number of Hanayama Cast puzzle designs to his name.

Comprising of just two irregular shaped pieces made of Finnish Curly Birch wood in a raw finish, the goal here is to form a symmetrical shape. The instructions are clear....to place the two pieces on a flat surface to form a symmetrical shape...no tricks, no silhouette, hole in centre and the like.

One would wonder how difficult can that be with just two pieces right? Wrong...it is in fact a rather difficult puzzle, more so if you don't even understand what a symmetrical shaperefers to.

During IPP33 itself, I had already seen quite a number of puzzlers in the competition room trying to figure this one out.... and many couldn't solve it even by the end of the event. All round it received a lot of positive comments. I took about a couple of hours before hitting the jackpot. Please PM me if you would like to see the solution...it's really quite unexpected.

Symmetrick IMHO is really an example of a great puzzle design, so simple and innocuous looking with just two pieces, yet very challenging. For those who love this sort of shape forming puzzles, its a must have. Available from Mr Puzzle Of Australia and Sloyd of Finland.

Four Triangles Five Shapes

This puzzle came courtesy of Emrehan Halici. I had a privilege of meeting Emrehan the second time during IPP35 in Ottawa last year and his Four Triangles Five Shapes (FTFS) was his exchange puzzle to me.

The FTFS is made of 3mm red laser cut acrylic. The four pieces comprise of four triangles of different shapes. Nicely cut and pretty large pieces so easy to handle.

There are five different tasks here (hence the name "five shapes"). Using all the triangles to make the following shapes:-

1. 3 different Pararellograms

2. An Isoceles triangle

3. A Square

I was able to make just one of the parallelograms, the isoceles triangle and the square...or so I thought. I shot an email to Emrehan for the solutions to the other two parallelograms and when he replied I was in for a shock; I had only gotten the square correct!

How difficult is the FTFS? Well, I only managed to solve one of the five shapes, despite just four pieces. I would rate it as very challenging indeed.As this one is an exchange puzzle, it's only available from the designer (assuming he has any left), so please PM me if you would like to get a copy and I will link you up with Emrehan.

Materials & ConstructionAcrylic, tespa, steel screws and a 1 Euro coin. Construction fit and finish is excellent and all the parts move smoothly with no jamming.

OverviewRobrecht is very well know for his "remove-the-coin" maze puzzles. And the best part is when you buy one of his puzzles, you get a 1 Euro discount! Unlike his other trapped coin puzzles, the Ladybird ups the ante in terms of sophistication of design and aesthetics. This time Robrecht encapsulates his puzzle within a ladybird design. Another main difference is that the Ladybird allows for some visibility of the maze route, hence you can see and feel your own progress. However, the Ladybird is no easier because the puzzle involves a double layer maze.The goal is to navigate two pins (connected to the two antennae) along both maze channels, by manipulating the two maze plates either clockwise or the opposite. Upon successful completion, you are rewarded with the 1 Euro coin that leaves through the circular cut-out on the top cover.

DifficultyModerate difficulty but tricky at times. The starting steps gives you a feel of what you need to do. I found that somewhere about a fifth along the way, If you do not get both pins in their right respective positions within the maze channels, you will find yourself stuck much later on and this would require an almost full backtrack. If you are lucky and get it right near the beginning, navigation becomes quite a breeze for a majority of the way. It took me a couple of attempts and one or two backtracks to finally extract the coin. Overall a fun puzzle and one of those that once you pick it up, you won't want to put it down until the coin comes out. Done correctly, it doesn't take too long to solve and reset. A really beautiful and interesting looking puzzle.